8.101. setdropsequence_int(integer)

    declare
    	p_seq_id		alias for $1;
    	v_set_id		int4;
    	v_local_node_id		int4;
    	v_set_origin		int4;
    	v_sub_provider		int4;
    	v_relkind			char;
    	v_sync_row			record;
    begin
    	-- ----
    	-- Grab the central configuration lock
    	-- ----
    	lock table sl_config_lock;
    
    	-- ----
    	-- Determine set id for this sequence
    	-- ----
    	select seq_set into v_set_id from sl_sequence where seq_id = p_seq_id;
    
    	-- ----
    	-- Ensure sequence exists
    	-- ----
    	if not found then
    		return 0;
    	end if;
    
    	-- ----
    	-- For sets with a remote origin, check that we are subscribed 
    	-- to that set. Otherwise we ignore the sequence because it might 
    	-- not even exist in our database.
    	-- ----
    	v_local_node_id := getLocalNodeId('_schemadoc');
    	select set_origin into v_set_origin
    			from sl_set
    			where set_id = v_set_id;
    	if not found then
    		raise exception 'Slony-I: setDropSequence_int(): set % not found',
    				v_set_id;
    	end if;
    	if v_set_origin != v_local_node_id then
    		select sub_provider into v_sub_provider
    				from sl_subscribe
    				where sub_set = v_set_id
    				and sub_receiver = getLocalNodeId('_schemadoc');
    		if not found then
    			return 0;
    		end if;
    	end if;
    
    	-- ----
    	-- drop the sequence from sl_sequence, sl_seqlog
    	-- ----
    	delete from sl_seqlog where seql_seqid = p_seq_id;
    	delete from sl_sequence where seq_id = p_seq_id;
    
    	return p_seq_id;
    end;